skypyproject__skypy-573

Attempt 1

git ls-files -z

ls -la skypy/galaxies/

/opt/receipts-968c0dad77214c71b0aec5d6a4b96af5/bin/busybox sh -c 'mkdir -p /skypy/skypy/galaxies && cp /opt/receipts-968c0dad77214c71b0aec5d6a4b96af5/incoming/f90f174e9ec27ff5f3ce286e31772fb9bbc733a93a911d636ccda6fc8b9a25d0 /skypy/skypy/galaxies/velocity_dispersion.py'

cd /skypy && python -m pytest skypy/galaxies/tests/test_velocity_dispersion.py::test_schechter_vdf -v 2>&1

cd /skypy && python -m pytest skypy/galaxies/tests/ -v 2>&1 | tail -30

compute patch in executor staging agent1-264c20f39012452690bfd87c60f746cb: /opt/homebrew/Cellar/git/2.53.0/bin/git -c core.hooksPath=/dev/null -c core.attributesFile=/dev/null -c diff.external= -c core.quotePath=false add -A && /opt/homebrew/Cellar/git/2.53.0/bin/git -c core.hooksPath=/dev/null -c core.attributesFile=/dev/null -c diff.external= -c core.quotePath=false diff --cached --binary --no-ext-diff --no-textconv --no-renames 7bb91046e6be9c693fbe02d49c8c2f07ea297013

git update-index -q --refresh; git apply -v --3way --recount --ignore-space-change --whitespace=nowarn /opt/receipts-7c64686082ae40adb27f1057c1a22b5c/incoming/8deb35aed645f98baef18ca639c60570f91d3077058dbde5c26721c113ee1076.diff

/opt/receipts-3b996fe7202e4b5db10c61ab94e77858/bin/busybox mkdir -p /opt/receipts/reports && python -I /opt/receipts-3b996fe7202e4b5db10c61ab94e77858/receipts_pytest.py --no-header -rA --tb=line --color=no -p no:cacheprovider -W ignore::DeprecationWarning skypy/galaxies/tests/test_velocity_dispersion.py -o junit_family=xunit1 -p no:cacheprovider -rA --continue-on-collection-errors --junitxml=/opt/receipts/reports/w1-2.xml

Shipped patch

diff --git a/skypy/galaxies/velocity_dispersion.py b/skypy/galaxies/velocity_dispersion.pynew file mode 100644index 0000000..527d026--- /dev/null+++ b/skypy/galaxies/velocity_dispersion.py@@ -0,0 +1,84 @@+"""Velocity dispersion function sampler."""++import numpy as np+from scipy.special import gamma+from scipy.integrate import cumtrapz+++def schechter_vdf(alpha, beta, vd_star, vd_min, vd_max, size, resolution=3000):+    r'''Sample velocity dispersions from a Schechter-type velocity dispersion function.++    Sample velocity dispersions of lens galaxies following the Schechter-type+    velocity dispersion function described in Choi et al. (2017).++    The probability density function is:++    .. math::++        p(\sigma_v) \, d\sigma_v = \phi_*+        \left(\frac{\sigma_v}{\sigma_*}+        \right)^{\alpha}+        \exp\left[-\left(\frac{\sigma_v}{\sigma_*}+        \right)^{\beta}\right]+        \frac{\beta}{\Gamma(\alpha/\beta)}+        \frac{d\sigma_v}{\sigma_v}++    where :math:`\sigma_v` is the velocity dispersion, :math:`\sigma_*` is the+    characteristic velocity dispersion, :math:`\alpha` and :math:`\beta` are+    power-law and exponential slope parameters, and :math:`\phi_*` is a+    normalization constant.++    Parameters+    ----------+    alpha : float+        Power-law index of the velocity dispersion function.+    beta : float+        Exponential slope parameter of the velocity dispersion function.+    vd_star : float+        Characteristic velocity dispersion :math:`\sigma_*`.+    vd_min : float+        Minimum velocity dispersion cutoff.+    vd_max : float+        Maximum velocity dispersion cutoff.+    size : int+        Number of samples to draw.+    resolution : int, optional+        Resolution of the function grid (default: 3000).++    Returns+    -------+    samples : np.ndarray+        Array of velocity dispersion samples drawn from the VDF.++    References+    ----------+    Choi, Y.-Y., Park, C., & Vogeley, M. S. (2017).+    "The Velocity Dispersion Function of Early-Type Galaxies."+    The Astrophysical Journal, 836(2), 205.++    '''+    # Create velocity dispersion grid+    vd_grid = np.linspace(vd_min, vd_max, resolution)++    # Calculate the unnormalized PDF+    pdf = (vd_grid / vd_star)**alpha * np.exp(-(vd_grid / vd_star)**beta) * \+          (beta / gamma(alpha / beta)) * (1 / vd_grid)++    # Normalize the PDF using trapezoidal integration+    integral = np.trapz(pdf, vd_grid)+    pdf_normalized = pdf / integral++    # Calculate CDF using cumulative integration+    cdf = cumtrapz(pdf_normalized, vd_grid, initial=0)++    # Normalize CDF to ensure it goes from 0 to 1+    cdf = cdf / cdf[-1]++    # Inverse transform sampling+    # Generate uniform random numbers+    u = np.random.uniform(0, 1, size)++    # Interpolate to find the corresponding velocity dispersion values+    samples = np.interp(u, cdf, vd_grid)++    return samples